Currently, multiple terminal devices such as a computer, a mobile phone, a tablet computer, a point of sale (Point of Sales, POS), and an in-vehicle computer each include a built-in display system, used to present a user interface (User Interface, UI) and implement human-machine interaction. A display panel included in the display system may be configured in a form of a liquid crystal display (Liquid Crystal Display, LCD), an organic light-emitting diode (Organic Light-Emitting Diode, OLED), or the like.
To ensure smooth display of the terminal device and avoid a frame loss, frameskip, or the like, the display system usually uses a vertical synchronization (Vertical Synchronization, Vsync) technology. A basic principle of the Vsync technology is that the display system generates a control signal at an interval of specified duration, so as to trigger a Vsync period. The specified duration is a value of the Vsync period, for example, 16 milliseconds (ms). When one Vsync period is triggered, the display system starts to process the following three procedures in parallel: an application drawing procedure, a surface (surfaceflinger) composition procedure, and a device display procedure. Original data that needs to be composited in the surfaceflinger composition procedure is a drawing result obtained in the application drawing procedure in a previous Vsync period, and data that needs to be displayed in the device display procedure is a composition result obtained in the surfaceflinger composition procedure in the previous Vsync period.
However, when the conventional Vsync technology is applied to the display system of the terminal device and each Vsync period is triggered, the display system needs to process the application drawing procedure, the surfaceflinger composition procedure, and the device display procedure in parallel. Consequently, transient power consumption of a central processing unit (Central Processing Unit, CPU) of the terminal device is relatively high, a CPU frequency is excessively high, and CPU working performance is reduced.